Course 3 9-5 Displaying Data A double-bar graph is used to display and compare two sets of data. You can organize data using a frequency table by listing items according to the number of times the items occur.

Additional Example 1: Displaying Data in a Double-Bar Graph Course 3 9-5 Displaying Data Additional Example 1: Displaying Data in a Double-Bar Graph Make a double-bar graph. The following are the number of books read in one month by some boys and girls in Grade 8. Books read 1 2 3 4 5 Boys Girls

Additional Example 1 Continued Course 3 9-5 Displaying Data Additional Example 1 Continued Make a double-bar graph. Frequency Books read The frequencies are the heights of the bars in the graph. Use a different color to represent each gender.

9-5 Displaying Data Check It Out: Example 1 Make a double-bar graph. Course 3 9-5 Displaying Data Check It Out: Example 1 Make a double-bar graph. The following are the number of tickets sold in one week by the boys and girls in Grade 8. Tickets Sold 5 10 15 20 25 Boys 3 9 8 2 Girls 4 6

Check It Out: Example 1 Continued Course 3 9-5 Displaying Data Check It Out: Example 1 Continued Make a double-bar graph. Frequency Tickets Sold The frequencies are the heights of the bars in the graph. Use a different color to represent each gender.

Course 3 9-5 Displaying Data A histogram is a bar graph that shows the frequency of data within equal intervals.

Additional Example 2: Displaying Data in a Histogram Course 3 9-5 Displaying Data Additional Example 2: Displaying Data in a Histogram Jimmy surveyed 12 children to find out how much money they received from the tooth fairy. Use the data to make a histogram. 0.35 2.00 0.75 2.50 1.50 3.00 0.25 1.00 1.00 3.50 0.50 3.00 First, make a frequency table with intervals of $1.00. Then make a histogram.

Additional Example 2 Continued Course 3 9-5 Displaying Data Additional Example 2 Continued 0.35 2.00 0.75 2.50 1.50 3.00 0.25 1.00 1.00 3.50 0.50 3.00 Money ($) Frequency 0 – 0.99 4 1.00 – 1.99 3 2.00 – 2.99 2 3.00 – 3.99 3

Additional Example 2 Continued Course 3 9-5 Displaying Data Additional Example 2 Continued Frequency Histograms do not have spaces between the bars. Helpful Hint

9-5 Displaying Data Check It Out: Example 2 Course 3 9-5 Displaying Data Check It Out: Example 2 Tonya surveyed 14 children at an after school day care to find out how many hours they spend there. Use the data to make a Histogram. 2:00 1:40 3:00 0:30 1:00 1:30 2:30 0:30 2:45 1:00 2:00 1:35 1:30 3:00 First, make a frequency table with intervals of 30 minutes. Then make a histogram.

Check It Out: Example 2 Continued Course 3 9-5 Displaying Data Check It Out: Example 2 Continued 2:00 1:40 3:00 0:30 1:00 1:30 2:30 0:30 2:45 1:00 2:00 1:35 1:30 3:00 Time Spent at Day Care Frequency 0:00 to 0:30 2 0:31 to 1:00 1:01 to 1:30 1:31 to 2:00 4 2:01 to 2:30 1 2:31 to 3:00 3

Check It Out: Example 2 Continued Course 3 9-5 Displaying Data Check It Out: Example 2 Continued Frequency Hours Spent at Day Care 1 2 3 4 5 0:00 to 0:30 0:31 to 1:00 1:01 to 1:30 1:31 to 2:00 2:01 to 2:30 2:31 to 3:00

Course 3 9-5 Displaying Data A double-line graph is used to show how two related sets of data change over time.

Course 3 9-5 Displaying Data Additional Example 3: Displaying Data in a Double-Line Graph Make a double-line graph of the given data. Use the graph to estimate the number of CDs and DVDs sold in 2003. The Music Shop CD and DVD Sales Year CD’s Sold DVDs Sold 1998 3002 735 2000 3098 1057 2002 4685 3010 2004 5804 4047

9-5 Displaying Data Additional Example 3 Continued Plot the data. Course 3 9-5 Displaying Data Additional Example 3 Continued Plot the data. The Music Shop CD and DVD Sales Number Sold Year The graph shows about 5,250 CDs and 3,500 DVDs were sold in 2003.

9-5 Displaying Data Check It Out: Example 3 Course 3 9-5 Displaying Data Check It Out: Example 3 Make a double-line graph of the given data. Use the graph to estimate the number of Strawberries and Figs grown in 2002. Perry's Strawberry-Fig Farm Sales Year Strawberry Baskets Sold Figs Sold 1999 4,000 1,200 2001 4,500 2,000 2003 8,000 3,500 2005 5,500 3,200

9-5 Displaying Data Check It Out: Example 3 Continued Plot the data. Course 3 9-5 Displaying Data Check It Out: Example 3 Continued Plot the data. Perry’s Strawberry-Fig Farm Sales Number Sold Year The graph shows about 6,250 Strawberry Baskets and 2,800 Figs were sold in 2002.

Insert Lesson Title Here Course 3 9-5 Displaying Data Insert Lesson Title Here Lesson Quiz: Part I 1. Make a histogram with intervals of 5 using the following data set: 7, 12, 8, 4, 4, 3, 6, 1, 14, 19, 8, 9 0-4 5-9 10-14 15-19 8 7 6 5 4 3 2 1 Frequency Units Frequency 0-4 4 5-9 5 10-14 2 15-19 1

Insert Lesson Title Here Course 3 9-5 Displaying Data Insert Lesson Title Here Lesson Quiz: Part II 2. Estimate the temperature on January 6 in 2004 and 2005 using the graph below. 2005: 31°C, 2004: 30°C

Insert Lesson Title Here Course 3 9-5 Displaying Data Insert Lesson Title Here Lesson Quiz: Part III Use the graph for problems 3–4. 3. On what day did both girls exercise for 30 minutes? Friday 4. On what day(s) did Ana exercise longer than Sue? Monday, Wednesday, Thursday, and Saturday

Scatter Plot A scatter plot is a graph of a collection of ordered pairs (x,y). The graph looks like a bunch of dots, but some of the graphs are a general shape or move in a general direction.

Positive Correlation If the x-coordinates and the y-coordinates both increase, then it is POSITIVE CORRELATION. This means that both are going up, and they are related.

Positive Correlation If you look at the age of a child and the child’s height, you will find that as the child gets older, the child gets taller. Because both are going up, it is positive correlation. Age 1 2 3 4 5 6 7 8 Height “ 25 31 34 36 40 41 47 55

Negative Correlation If the x-coordinates and the y-coordinates have one increasing and one decreasing, then it is NEGATIVE CORRELATION. This means that 1 is going up and 1 is going down, making a downhill graph. This means the two are related as opposites.

Negative Correlation If you look at the age of your family’s car and its value, you will find as the car gets older, the car is worth less. This is negative correlation. Age of car 1 2 3 4 5 Value $30,000 $27,000 $23,500 $18,700 $15,350

No Correlation If you look at the size shoe a baseball player wears, and their batting average, you will find that the shoe size does not make the player better or worse, then are not related.

Which scatterplots below show a linear trend? Negative Correlation Positive Correlation b) d) f) Constant Correlation

Objective - To plot data points in the coordinate plane and interpret scatter plots. y Sport Utility Vehicles (SUVs) Sales in U.S. 5 4 3 2 1 Year Sales (in Millions) 1991 0.9 1992 1.1 Vehicle Sales (Millions) 1993 1.4 1994 1.6 1995 1.7 1996 2.1 1997 2.4 1998 2.7 1991 1993 1995 1997 1999 1992 1994 1996 1998 2000 x 1999 3.2 Year

Scatterplot - a coordinate graph of data points. y Trend appears linear. 5 4 3 2 1 Trend is increasing. Vehicle Sales (Millions) Positive correlation. Predict the sales in 2001. 1991 1993 1995 1997 1999 1992 1994 1996 1998 2000 x Year

Plot the data on the graph such that homework time is on the y-axis and TV time is on the x-axis.. Time Spent Watching TV Time Spent on Homework Student Sam 30 min. 180 min. Jon 45 min. 150 min. Lara 120 min. 90 min. Darren 240 min. 30 min. Megan 90 min. 90 min. Pia 150 min. 90 min. Crystal 180 min. 90 min.

Plot the data on the graph such that homework time is on the y-axis and TV time is on the x-axis. TV Homework 240 210 180 150 120 90 60 30 30 min. 180 min. 45 min. 150 min. 120 min. 90 min. Homework Time on 240 min. 30 min. 90 min. 120 min. 150 min. 120 min. 180 min. 90 min. 30 90 150 210 60 120 180 240 Time Watching TV

Describe the relationship between time spent on homework and time spent watching TV. Trend appears linear. 240 210 180 150 120 90 60 30 Trend is decreasing. Homework Time on 30 90 150 210 60 120 180 240 Negative correlation. Time Watching TV